This application requests support for continuation of ongoing studies of the classification, development, inheritance of alcohol abuse in Swedish adoptees. The major goals of the proposed study are (1) to carry out a replication of the Stockholm Adoption Study of the inheritance of alcohol abuse in a independent sample of over 1500 adoptees born in Gothenburg, Sweden from 1917-1965, and (2) to conduct a prospective longitudinal follow-up at age 36 years of children registered for adoption in 1956-57, previously evaluated in infancy and at 11, 15, 18, 23, and 27 years. Tests of explicit hypotheses derived from prior work and a neurobiological learning model of susceptibility to alcoholism will be carried out. Specifically, in the Gothenburg adoption study predictions about the heritable risk of alcohol abuse and related disorders in adoptees will be based on classification of biological parents according to specific subtypes of alcoholism, as well as the postnatal adoptive home environment. Furthermore, in the prospective study, prediction of alcohol abuse will also be based on ratings of childhood personality traits of novelty seeking, harm avoidance, and reward dependence, as well as the other biological and adoptive risk factors. Analyses will be carried out to determine whether childhood personality traits provide additional information about adult risk of alcohol abuse in adopted-away children beyond that provided by alcohol abuse in their parents. Antisocial personality traits (high novelty seeking, low harm avoidance, and low reward dependence) have already been shown to predict early onset alcohol abuse (mostly type 2) by follow-up through age 27. The proposed follow-up to age 36 years would test the prediction that the opposite configuration (anxious traits or high reward dependence, high harm avoidance, and low novelty seeking) personality traits antecede late onset (mostly type 1) alcohol abuse. The studies are expected to provide tests of theoretically specified hypotheses and to clarify prior information about the nosology, natural history, and etiology of alcoholism.